A surge in killings has pushed up the District’s homicide count this year, a spike that is worrying residents, police and city leaders as the summer gets underway.

Nearly 30 people have been killed since May 1, double the number during the same period last year, and 14 have been killed in the past 17 days. This year’s homicide count stands at 64, compared with 53 at this time last year.

The increase comes as the department is dealing with the departure of about 500 officers over the past 18 months and amid investigations into several high-profile ­cases, including the slaying of three members of the Savopoulos family and their housekeeper.

D.C. Police Chief Cathy L. Lanier said detectives “don’t see any discernible patterns” in the cases, which are spread over every quadrant of the District. “The bottom line is that it is arguments that result in violence,” Lanier said. “Most seem to be over very petty issues.”

Six killings this year were domestic related, Lanier said, and many homicides involved stabbings rather than guns. The chief said there were fewer shootings and assaults with deadly weapons. “Overall, the violence is down,” she said. “The lethality of the violence is up.”

And the District’s homicide count could rise even further after the medical examiner rules on the cause of death for bodies and human remains found this week. A body found in a burning trash can in Trinidad was ruled a homicide Thursday, bringing the total to 64. Police are awaiting rulings on a body found in a creek and another floating in the Tidal Basin. Human remains were pulled from the Potomac River near the Kennedy Center.

In an interview, two D.C. police officers described investigators as being strapped. “We’re responding from scene to scene,” one officer said. “It may take a week or two longer now to investigate a case, because we have a new case. . . . We were on one case when we got a call for a new case and then have to put that case to the side.”

The officers spoke on the condition of anonymity because it is against department policy to speak to the news media without permission from commanders.

Lanier said that even with the loss of officers over the past 18 months, she is redeploying to keep the front-line patrol unit up to strength in the face of the rising homicide count. While noting that 190 officers are going through the police academy, she said that keeping up with attrition is a struggle.

The chief is promising to ramp up efforts to curtail the violence through targeted street patrols and other less-visible initiatives, and she said a new squad of detectives targeting drug dealers and narcotics such as PCP and synthetic drugs has hit the streets.

Lanier joined Mayor Muriel E. Bowser (D) at a community meeting at the 5th District police station in Northeast Washington on Thursday night to explain the city’s efforts to put more officers on streets and to work with federal officials to help curb violence.

Mapping homicides in the District and the surrounding suburbs since 2000.

“The chief has been very focused on being responsive to the spike in crime that we have seen and is troubling to all of us,” Bowser told those in attendance. “We are very concerned about the increase in crime related to guns and certainly very concerned about the increase in homicides.”

On Saturday afternoon, Bowser held a conference call with acting U.S. attorney Vincent Cohen and U.S. Parole Commissioner Patricia Smoot to discuss anti-crime efforts.

Bowser also held a meeting Tuesday with her public safety team and several federal law enforcement representatives.

Lanier plans to launch her “All Hands On Deck” initiative at the end of August, a weekend in which all leave is canceled and every available officer is put on street patrol. The chief says crime drops as much as 28 percent during such 48-hour deployments; the D.C. police union calls the program illegal under labor laws and disputes its effectiveness.

Delroy Burton, the union’s chairman, blamed part of the homicide spike on difficulties in filling positions and on what he called a tough atmosphere given the backlash against police in Baltimore and other communities after deaths in police custody. He said 502 officers had left the 4,000-member D.C. department since January 2014.

The talk about crime strategies and increased patrols “won’t matter if we’re losing people faster than we can bring them in,” Burton said. He added that “our integrity is being questioned. Our tactics are being questioned. Police are getting worried about getting in trouble for every little thing. It’s not an atmosphere that encourages aggressive, proactive policing.”